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    <div class="example" id="channel-buffering">
      <h2><a href="./">Go by Example 中文版</a>: 通道缓冲</h2>
      
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            <p>默认情况下，通道是 <em>无缓冲</em> 的，这意味着只有对应的接收（<code>&lt;- chan</code>）
通道准备好接收时，才允许进行发送（<code>chan &lt;-</code>）。
<em>有缓冲通道</em> 允许在没有对应接收者的情况下，缓存一定数量的值。</p>

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            <a href="http://play.golang.org/p/4grWiuPaz0b"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
          <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
</pre></div>

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          <div class="highlight"><pre><span class="kn">import</span> <span class="s">&quot;fmt&quot;</span>
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          <div class="highlight"><pre><span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
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            <p>这里我们 <code>make</code> 了一个字符串通道，最多允许缓存 2 个值。</p>

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          <div class="highlight"><pre>    <span class="nx">messages</span> <span class="o">:=</span> <span class="nb">make</span><span class="p">(</span><span class="kd">chan</span> <span class="kt">string</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
</pre></div>

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            <p>由于此通道是有缓冲的，
因此我们可以将这些值发送到通道中，而无需并发的接收。</p>

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          <div class="highlight"><pre>    <span class="nx">messages</span> <span class="o">&lt;-</span> <span class="s">&quot;buffered&quot;</span>
    <span class="nx">messages</span> <span class="o">&lt;-</span> <span class="s">&quot;channel&quot;</span>
</pre></div>

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            <p>然后我们可以正常接收这两个值。</p>

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          <div class="highlight"><pre>    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="o">&lt;-</span><span class="nx">messages</span><span class="p">)</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="o">&lt;-</span><span class="nx">messages</span><span class="p">)</span>
<span class="p">}</span>
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          <div class="highlight"><pre><span class="gp">$</span> go run channel-buffering.go 
<span class="go">buffered</span>
<span class="go">channel</span>
</pre></div>

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        下一个例子: <a href="channel-synchronization">通道同步</a>
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